1. Field of the Invention
The present invention relates generally to medical equipment, and more particularly, to an automated apparatus for cleaning a cannula so that it may be reused to reconstitute one or more medications that are prepared in a vial and stored in a syringe.
2. Discussion of the Related Art
Disposable syringes are in widespread use for a number of different types of applications. For example, syringes are used not only to withdraw a fluid (e.g., blood) from a patient, but also to administer a medication to a patient. In the latter, a cap or the like is removed from the syringe and a unit dose of the medication is carefully measured and then injected or otherwise disposed within the syringe.
As technology advances, more and more sophisticated, automated systems are being developed for preparing and delivering medications by integrating a number of different stations, with one or more specific tasks being performed at each station. For example, one type of exemplary automated system operates as a syringe filling apparatus that receives user inputted information, such as the type of medication, the volume of the medication and any mixing instructions, etc. The system then uses this inputted information to disperse the correct medication into the syringe up to the inputted volume.
In some instances, the medication that is to be delivered to the patient includes more than one pharmaceutical substance. For example, the medication can be a mixture of several components, such as several pharmaceutical substances.
By automating the medication preparation process, increased production and efficiency are achieved. This results in reduced production costs and also permits the system to operate over any time period of a given day with only limited operator intervention for manual inspection to ensure proper operation is being achieved. Such a system finds particular utility in settings, such as large hospitals, where a large number of doses of medications have to be prepared daily. Traditionally, these doses have been prepared manually in what is an exacting but tedious responsibility for a highly skilled staff. In order to be valuable, automated systems must maintain the exacting standards set by medical regulatory bodies, while at the same time simplifying the overall process and reducing the time necessary for preparing the medications.
Because syringes are often used as the carrier means for transporting and delivering the medication to the patient, it is advantageous for these automated systems to be tailored to accept syringes. However, the previous methods of dispersing the medication from the vial and into the syringe were very time consuming and labor intensive. More specifically, medications and the like are typically stored in a sealed vial. A conventional vial is formed of a body (i.e., glass) and is sealed with a membrane across the open end of the body. The membrane can be formed of any type of material that is typically used in this setting for sealing a container (e.g., vial) yet at the same time permit a user to puncture or pierce the membrane with an instrument to gain access to the inside of the container. In one exemplary embodiment, the membrane is formed of a rubber material that can be easily stretched across the open end while still providing the necessary seal.
A safety cap is securely attached to the vial to cover the exposed membrane and further seal the open end of the vial body. The safety cap is typically formed of a light, disposable material, such as a plastic, and is attached at the end in a tamper proof manner. For example, the safety cap is attached so that once it is removed, it can not be re-attached to the vial body. Thus, a vial that does not contain a safety cap is easily recognizable and indicates that either (1) the safety cap has previously been removed and medication in the vial has been withdrawn, (2) the safety cap was not properly attached and has accidently become displaced, (3) the vial has been tampered with, etc. In any event and unless the exact history of the particular vial is know, any vial that is missing a safety cap is ordinarily discarded and not used.
It will be understood that the parts of the vial are merely exemplary in nature and the many different tamper proof vial constructions are available. The common elements are that the vials each contain a membrane and the safety cap is easily removable but at the same time provides further protection of the membrane and also serves as an indicator of whether the vial has been used.
In conventional medication preparation, a trained person retrieves the correct vial from a storage cabinet or the like, confirms the contents and then removes the safety cap manually. This is typically done by simply popping the safety cap off with ones hands. Once the safety cap is removed, the trained person inspects the integrity of the membrane and cleans the membrane. An instrument, e.g., a cannula, is then used to pierce the membrane and withdraw the medication contained in the vial. The withdrawn medication is then placed into a syringe to permit subsequent administration of the medication from the syringe. Often, the membrane is first pierced with an instrument for injecting a diluent into the medication prior to withdrawal of the medication. This is a very time and labor intensive task. Thus, what is needed in the art and has heretofore not been available is a system and method for automating the medication preparation process and more specifically, an automated system and method for cleaning a cannula so that it can be reused numerous times to prepare different medications in different vials and then to transfer those medications to syringes so the medication can be administered to a patient.
In accordance with an exemplary embodiment of the present invention this and other needs are achieved with a computer-implemented method and system for cleaning a contaminated cannula so that it may be reused. The method and system include moving the contaminated cannula from a drug reconstitution station where the cannula is used to prepare a drug solution into a first rinsing station where the cannula is cleaned. A database is referred to determine what drug solution the cannula has been contaminated with, and to determine a first amount of cleaning fluid that needs to be passed internally through the cannula, and a second amount of cleaning fluid that needs to be passed externally about the cannula so that there is effectively no contaminant remaining on the inside surface and the outside surface of the cannula. The first amount of cleaning fluid is passed internally through the cannula. The second amount of cleaning fluid is passed externally about the cannula. After the cannula is cleaned, the cannula is moved to the drug reconstitution station to prepare another drug solution.